In early design phases of architecture ideas exist mostly on a vague level concerning the expectations for the building plan and the respective design parameters. One established method is to examine and develop ideas through existing designs, and to use these to clarify design parameters and be further inspired. Thus, the aim is a computer-based system like sketch-based query approach to show similar floor plans using semantic building fingerprints.During the search floor plans are compared in form of graphs, which means that the sketch-based floor plans are converted to graphs together with the existing floor plans. Herewith, a gradual condensation of the request is possible. The entry is condensed continuously through the repetitive process of entry and search. The challenges with this approach lie in the following mathematical model behind similar floor plans, Queries that satisfy complexity of the data and optimal way for the user to engage in search process.